196 BULLETIN 121, UNITED STATES NATIONAL MUSEUM. 



quence of plumages, but apparently the fully adult plumage is not 

 completed until the second winter or later. 



Food. — Mr. A. J. Campbell (1901), referring to the flight and 

 feeding habits of this booby, quotes the following observation of Mr. 

 F. M. Hobbs, of Norfolk Island: 



I think the gannet is the clumsiest on the ground of all the birds which fre- 

 quent this locality, but once it gets on the wing, it seems one of the proudest. 

 I have often watched them from the whaling boats darting down after their 

 prey. They descend at a wonderfully rapid rate, and must go to a considerable 

 depth below the surface of the water, for they keep under for a long time. The 

 flying fish seem to be their favorite food, but I have never seen a gannet pursue 

 them while they (the fish) are flying. 



Its most troublesome enemy seems to be the man-o-war bird, as the 

 following incident, related by Dr. Homer R. Dill (1912) will illu- 

 strate : 



Not far from this spot we saw a man-o-war bird pursuing a booby which had 

 just returned from fishing, with a crop full of fish. At first it seemed as though 

 the booby would outfly its pursuer, but its load was too heavy. The man-o-war 

 bird overtook the booby, seized it by the tail, raised itself in the air, an<l 

 turned the booby completely over. Being thus rudely overturned the booby lost 

 control and quickly disgorged the contents of its crop, and the man-o-war bird 

 actually caught the fish as it came from the booby's mouth. 



Behavior. — Messrs. Snodgrass and Heller (1902), referring to the 

 habits of the blue-faced booby in the Galapagos Islands, say : 



The most common note uttered by the adults was a loud quack. Occasionally 

 a sharp whistle was heard, but no special significance to this sound was observed. 

 The species was observed fishing at sea, 300 miles from the island, and it is 

 probable that the birds, in pursuit of food, daily travel more than 100 miles 

 from their breeding grounds. 



DISTRIBUTION. 



Breeding range.— On some of the Lesser Antilles (the Grenadines, 

 [Battowia and Kick-em- Jenny] ) and off the coasts of Venezuela (Los 

 Hermanos Islands), Colombia (Gorgonall Islands) and Yucatan 

 (Alacron Reefs). Formerly on the Bahama Islands (Santo Do- 

 mingo Key). 



Birds which breed in various islands in the Pacific and Indian 

 Oceans, from the coast of Mexico westward have now been subdi- 

 vided into other subspecies. 



Winter raJ^^e.— Practically the same as the breeding range, within 

 30' of the equator. 



Casual records.— ^2iidi to be accidental in southern Florida. Taken 

 once in Louisiana (Avery Island, August, 1915). 



Egg tfojifes.— Mexican Islands: Twelve records, March 20 to May 

 21 ; six records, April 26 to May 21. 



